Patent GB-1206493-A (GB)
Title: Opposed jaw fastener
IPC: E05C19/00
Filed: 1968-10-01
Abstract: 1,206,493. Releasable fastenings. HARTWELL CORP. 1 Oct., 1968 [5 Oct., 1967], No. 46427/68. Headings E2A and E2B. An opposed jaw fastener with a keeper 29 having an engageable surface 32 comprises a pair of levers 15 mounted in relatively pivoted relation, adjacent end portions of said levers forming a pair of jaws 18, 19 for movement to and from each other to engage said engageable surface of. the keeper member, a housing for said levers, a first means 6 carried by said housing and associated with said levers for effecting movement of the levers in unison with respect to said housing; second means 4 carried by said housing and engaging said levers for spreading said jaws to pass said keeper when said levers are each at one extreme translational position, and for holding said jaws in engagement with the keeper when said levers are each at the other extreme translational position; and third means 25 for biasing said jaws toward one another. In the construction shown the levers are pivotally connected by a pivot pin 13 and the end portions of the pin pass through slots 14 in opposite side walls of the housing to guide the levers during their translating movement. The housing is made in two parts each of which is of channel section, the two parts being connected together by a pair of tubular rivets 4, the upper one of which constitutes the second means above being on the one side of the pivot pin 13 and the other rivet 4 on the other side. The first means 6 is a slide carried in slots in the end walls of the housing for movement transversely to the translating movements off the levers, the slide having a slot 8 which, as shown, has a horizontally extending land 9 joined by a sloping ramp portion 11 to a second horizontally extending land 10 which in turn is connected to a second sloping ramp portion 12; when the pivot pin 13 is in the land 9 the levers are in a fastening position in which the jaws are engaged with the keeper and the second rivet is disposed between the levers in engagement with shoulders 23 so that the jaws cannot move to release the keeper; movement of the slide to the left as shown engages the ramp portion 11 with the pivot pin 13 and this causes translating movement of the two levers so that the jaws move away from the housing end portion and as the pivot pin is engaged by the second ramp portion 12, cam surfaces 22 of the levers become engaged with the first rivet 4 and hence continued translating movement of the levers causes spreading of the jaws to release the keeper. Initial movement of the slide to the right allows the jaws to close under the urge of the third means 21 (which as shown is a spring) as the pin is moved downwardly by the ramp portion 12 and when it is in the ramp portion 10 the jaws remain closed but they can be parted against the bias of the spring by pressure between the jaws and a conical face of the keeper so that the jaws can thus become engaged with the keeper; continued movement of the slide to the right causes the engagement of the pin by the ramp portion 11 which continues the translating movement downwardly so that the second rivet 4 can enter between the jaws and become engaged with the shoulders 23 when the pin enters the horizontal portion 9. The slide has a slot 26 with a retainer tongue 27 the slot receiving a spring 28 which biases the slide to the position in which the pivot pin is in the portion 10 from the position in which the jaws are spread apart. In a modification the portion 10 of the slot is omitted so that there is a single ramp portion instead of two and the keeper does not have a conical end face so that to engage the jaws with the keeper the jaws must be spread apart by using the slide.